This invention relates to an electronic metering faucet. It relates more particularly to a faucet of this type which is preferably activated by touch and/or proximity to the faucet and which has a consistent water delivery period over the life of the faucet.
There are several different types of metering faucets in use today. Many are manually activated to turn on the water by pressing the faucet head and are hydraulically timed so that the water remains on for a set period of time after depression of the head. Some of these faucets have separate head allowing separate control over the hot and cold water. Other metering faucets mix the incoming hot and cold water streams and, when actuated, deliver a tempered output stream.
Also known is a manually activated metering faucet whose on-time is controlled electronically. Still other known faucets are activated electronically when the user positions a hand under the faucet. These faucets usually incorporate an infrared or ultrasonic transceiver which senses the presence of the user""s hand and turns the faucet on so long is that the hand remains under the faucet.
The aforesaid hydraulically timed faucets are disadvantaged in that it is difficult to accurately control the on-time of the faucet over the long term because of mains pressure changes and foreign matter build up in the faucet which can adversely affect the hydraulic controls within the faucet. On the other hand, the known electronic faucets can not always discriminate between a user""s hand and other substances and objects which may be brought into proximity to the faucet, e.g. a reflective object disposed opposite the faucet""s infrared transceiver, soap build up on the faucet""s proximity sensor, etc. Resultantly, those prior faucets may be turned on inadvertently and/or remain on for too long a time resulting in wastage of water.
Still other conventional metering faucets are relatively complicated and therefore costly to manufacture.
Accordingly, it is an object of the present invention to provide an improved electronic metering faucet.
Another object is to provide a faucet of this type which is electronically timed and maintains its timing accuracy over the life of the faucet.
A further object of the invention is to provide an electronic metering faucet which may be touch activated.
Still another object of the invention is to provide a self-contained battery operated electronic metering faucet which can operate for over three years between battery replacements.
Another object is to provide such a faucet which has a minimum number of moving parts.
A further object of the invention is to provide a touch activated electronic metering faucet which can be manufactured at relatively low cost.
Another object is to provide a faucet whose parts may be accessed quite easily for maintenance purposes.
Still another object of the invention is to provide a faucet of this general type which is activated by single touch sensor to produce a timed and tempered water stream.
Other objects will, in part, be obvious and will, in part, appear hereinafter. The invention accordingly comprises the features of construction, combination of elements and arrangement of parts which will be exemplified in the following detailed description, and the scope of the invention will be indicated in the claims.
Briefly, the metering faucet is a touch activated, electronically timed faucet that can deliver water at a selected temperature for a preset water delivery period which, unless reset, remains substantially constant, i.e. within 2%, over the faucet""s life span. The faucet includes a simple non-water-contacting housing or encasement which is adapted to be secured to a sink or countertop. Supported in the housing is a single cartridge containing most of the hydraulic components of the faucet including a solenoid-actuated valve which controls the delivery of water from hot and cold water lines to a single outlet at the end of a faucet spout formed by the housing. The housing or encasement also supports a stationary faucet head which contains all of the electrical components necessary to actuate the valve for a selected period of time after a user""s hand touches or is moved into close proximity to a selected target area on the head.
As we shall see, the faucet includes provisions for preventing inadvertent faucet activation by non-environmental factors such as soap build up, contact by paper towels, etc., as well as accidental human contact. This is accomplished by dynamically adjusting in real time the faucet""s activation sensitivity depending upon the prevailing conditions. Once activated, the faucet will deliver a stream of water at a set temperature for a predetermined time period. At the end of that period, the faucet""s internal controls will issue a shut-off command which positively shuts off the faucet""s solenoid valve.
Further as we will come apparent, the faucet is designed so that its components can readily be made and assembled and be accessed quiet easily by maintenance personnel for repair purposes. Still, the faucet can be made in quantity at a relatively low cost.